Amid the time of the Clone Wars, a Haven-class medical station was utilized by the Galactic Republic as a medical center and located in Sector 11. However, sometime during the reign of the Galactic Empire following the war's end, the space station was decommissioned, with several systems becoming corrupted over time. Later, in 4 BBY, the Haven-class medical station was visited by members of the Spectres, who were in search of medical supplies for their allies in the Phoenix rebel cell. However, during their mission, the rebels were ambushed by the Fifth Brother and Seventh Sister of the Empire's Inquisitorius. Despite the efforts by the Inquisitors to capture their adversaries, the rebels were able to escape with a crate of supplies, returning to the rebellion afterward.
Like other space stations of its class, the Haven-class medical station consisted of an elongated central shaft with eight spokes that formed the Republic crest when viewed from above. Despite having been abandoned for some time by the time members of the Spectres visited in 4 BBY, the station was still in good enough shape to be fully powered up, even though there was garbage strewn throughout the hallways. The station also still possessed medical supplies that could be salvaged.
The medical station was built for use by the Galactic Republic during the Clone Wars against the Confederacy of Independent Systems. After the end of the galaxy-spanning conflict, the station was abandoned, although in good condition with useful medical supplies still onboard. In 4 BBY, the Galactic Empire sent Inquisitors, Force-sensitive agents, to hunt down the Jedi members of the Spectres, a crew of rebels who were part of the Phoenix Cell. One of the Inquisitors, Seventh Sister, planted ID9 seeker droids in the station to monitor it, as she felt that the rebels might appear there.
Meanwhile, with the rebels in need of medical supplies, Hera Syndulla, leader of the Spectres, dispatched Garazeb Orrelios, Sabine Wren, and Chopper to search the station, based on intel from clone trooper Captain Rex, who also gave them access codes for the station. Padawan Ezra Bridger, desperate for a chance to briefly escape his Jedi training, decided to come along as well, and the group departed on the shuttle Phantom.
The Seventh Sister interrogates Bridger in the station control room.
Arriving at the station, the Phantom landed in a hangar after the access codes worked to open the door. The rebels ventured deeper into the station, with Wren in particular unnerved by the station's atmosphere, which she found creepy. Bridger suggested the station as a potential base for the Phoenix rebels, but Wren shot his idea down. Reaching a control room, Wren had Chopper activate a terminal, but the astromech droid instead turned on power to the entire station before Wren had him switch most of it off. The brief power surge triggered alarms on the Star Destroyer that Imperial Admiral Kassius Konstantine, Imperial Security Bureau Agent Alexsandr Kallus, and the Inquisitor Fifth Brother were aboard. Fifth Brother, sensing that a Jedi was likely involved, refused assistance and set off by himself for the station.
Chopper searched the station's computers for the location of any remaining supplies, but found that the computers' remaining data had become corrupted and unreadable, so the rebels split up and began searching for themselves. Orrelios and Bridger, getting into an argument, missed a storage room containing crates of medical supplies as they decided to race each other to see who could find supplies first. Wren was spotted by some of the seeker droids, but did not notice she was being watched. The droids subsequently alerted Seventh Sister of the intruders, before one lured Chopper into a trap and electrocuted him, using the droid to send a distress transmission to the other rebels.
The two Inquisitors arrived at the station around the same time, each unaware of the other's presence, and began seeking out the rebels. Bridger and Wren entered a ventilation shaft in order to reach Chopper quickly; Orrelios attempted to follow but, being much larger, became stuck. Upon getting to the upper level, Bridger and Wren quickly encountered the Seventh Sister and her droids, and were overwhelmed and forced to flee. During their flight, they encountered the Fifth Brother and were subsequently separated when Bridger sealed a door in order to assist Wren in escaping. The Padawan was subsequently captured, with the Seventh Sister making it clear to her colleague that they could capture the other rebels if they kept him alive.
The medical station first appeared in the 2015 Star Wars Rebels season 2 episode "Always Two There Are."